Zion 660 - tire clearance test

Just picked up a new geared Zion 660 steel hardtail from from Jenson while they're running their "free" shipping deal for purchases over $150. (Warning - they will still charge you $15 shipping for "oversize" items like wheels and frames, so it's not really free now is it? )

I've owned a fair number of steel hardtail frames and this one appears pretty standard by Taiwan-built standards. Decent welds, pretty straight, nice dropouts, 4130 tubing. I didn't weigh the frame bare before I built it, but Jenson lists this 19" frame at 4.6 lbs. (Based on the final weight of the bike, compared to the frame I had these components on, I'd guess it's closer to 5 lbs than 4.6, but at $249 I'm not complaining.) It came together pretty nice. The parts are far nicer than the bike, but this frame is intended as a stop-gap until I can afford a custom-built steel frame next year.

Anyway, the rap on these Zion frames, including the Zion 853 from last year and this year's 660 (they went away from Reynolds 853 tubing to 4130 chromo) is rear tire clearance. People p!ss and moan that they can't run anything larger than 2.1 as a back tire due to the lack of clearance between the chainstays. So, before I take mine for its first ride tomorrow, I thought I'd test 5 different tires that have marked tread widths from 2.1 to 2.4 to see how big you can go before you get chainstay rub. (I'm well aware that the marked tire size is rarely the actual tire size. That's why I always consult Shiggy's comprehensive tire size chart before I ever buy a tire so I know exactly what the real specs are on a tire. That Shiggy, he's a smart one.)

All tires were of the tubed variety, mounted on a Mavic 717 disc rim, and aired up to approximately 38 psi. I started with a Kenda Nevegal 2.1 in the Stick-E compound. According to Shiggy's site, this is a true 2.1 tire (if not larger). Plenty of clearance.

Next up was an IRC Trailbear 2.25. I can't find the specs for this tire on Shiggy's site, but it looks maybe a little narrower than a true 2.25. Maybe between 2.15 and 2.2. Plenty of clearance.

Third I tried a WTB Weirwolf 2.3. This tire has a fairly narrow casing for its stated size, and isn't a real tall tire. Guess what? It fit, but a little tighter than the Trailbear.

I decided to press my luck with tire # 4 - I tried the Kenda Nevegal 2.35 in the Stick-E compond. This is, I think, a true 2.35 tire. No way this thing is going to fit I thought. Wrong. It was tight, maybe 2-3 mm of clearance on either side of the tire, but the wheel spun freely with no rub. That said, it probably would rub if the stays flexed under pedaling.

For tire # 5, I tested my favorite summertime tire for the conditions I ride - the WTB Mutanoraptor 2.4. Now, this is definitely not a true 2.4. According to Shiggy, it has a casing width similar to most true 2.4 tires (measured on his site of 2.09) but it has very minimal tread that also measures on Shiggy's site at 2.09. I love this tire for dry hardpack - it's light and rolls well. Amazingly enough, even though it probably measures narrower than the 2.3 Weirwolf, it's such a tall, high volume tire, that it came the closest to rubbing the stays. It rolled, but it was so close to the stays that I'm sure if the stays flexed at all it would seriously rubbed.

All in all, if you can find a wide tire that isn't too tall or super high-volume, it should fit the Zion just fine. I ended up going with the Kenda 2.1 (with the 2.35 Kenda on the front) for my summer tire choice. Winter, I'll probably switch to the Trailbear in the back and a 2.35 Blue Groove up front. Can't wait to see how it rides. (I would guess it rides like a hardtail. )

Yeah, HardDrive tried 2.0 Scorpions in his, which are more like 2.2's and they fit in, with a little room to spare. It's an XC hardtail after all, so I don't know why people expect it to fit 2.5's etc...

I've ridden an Access XCL and you NEED big cushy tires to make it comfy enough to ride. It is one stiff mutha. I'm guessing the Zion will have slightly more give. I also remember that my old Gunnar Rockhound frame didn't even have the tire clearance that the Zion has.

I have a Klein Pinnacle that you'd think would be an ass beater, but it's not too bad, even with a miserable old 1.9 Wildgripper on the back. My Taos really surprised me with it's gentle nature too, but I'm running big 2.0 Spiders and a Ti rail WTB seat for a little give. My GT Avalanche is far harsher than either bike, depsite its much smaller stays. Could have something to do with the Triple Triangle. After 12 years of alloy hardtails my ass is prolly numb anyway....

have you tried the mutano 2.24. Ive heard there is a big difference between the the 2.24 and 2.4. I even heard the 2.4 is lighter because the 2.24 has thicker tread. I dont know... but Im thinking getting a the 2.24 but everyone talks about the 2.4

Faced and chased????????

Originally Posted by Earthpig

I've ridden an Access XCL and you NEED big cushy tires to make it comfy enough to ride. It is one stiff mutha. I'm guessing the Zion will have slightly more give. I also remember that my old Gunnar Rockhound frame didn't even have the tire clearance that the Zion has.

Not to rip off the thread.....Did the Zion frame come faced and chased?
Thanks,
Dave